飞机飞越噪声自由场声压级测试方法研究  

Investigation of Measurement Methods to Obtain Free-field Sound Pressure Levels of Airplane Flyover Noise

作　　者：朱江辉[1,2] ZHU Jianghui(Chinese Flight Test Institute,Xi′an 710089,China;School of Automation,Northwestern Polytechnical University,Xi′an 710072,China)

机构地区：[1]中国飞行试验研究院,西安710089 [2]西北工业大学自动化学院,西安710072

出　　处：《噪声与振动控制》2023年第4期280-287,共8页Noise and Vibration Control

摘　　要：在飞机飞越噪声地面试验中,噪声测量受地面对声波散射的较大影响。为修正地面对飞越噪声测量的影响,开展飞行试验对飞越噪声自由场声压级测试技术的研究。首先,进行地面对飞机飞越噪声传播的影响分析,推导获取自由场声压级的修正方法,仿真分析影响因素。随后,设计三类可消除地面影响获得自由场声压级的飞越噪声测试方案,应用于某大型运输类民机的飞越噪声测试飞行试验,分析测试方案的适用性。试验结果表明,地面对飞越噪声测量有不可忽略的影响,提出的噪声测量方案均能在一定的宽频带内取得自由场声压级,其中采用带有声学硬反射面的传声器布置方式,在中低频段的宽频带的自由场声压级修正量约为+6 dB,采用加高布置传声器的方式在中高频段的自由场声压级修正量约为+2.8 dB,据此可简便、可靠地得到飞越噪声的自由场声压级,而针对不同的试验条件,需采用与之相适应的测量方法。The airplane flyover noise measured by microphones mounted above ground contains the interference of sound wave scattering of ground surface.In order to analyze such an effect and obtain free-field sound pressure levels of aircraft flyover noise,the measurement methods of the noise are inquired.On the basis of analytical solutions of sound wave reflection of the ground surface,the expression of correlation factor of the free-field sound pressure level is presented.Then,three types of noise measurement methods of mounting the microphones on the ground surface and elevated poles etc.are recommended to eliminate the ground interference effect and obtain free-field sound pressure levels.The methods are verified by a civil airplane flyover noise flight tests.The results show that the ground surface has significant impact on flyover noise measurement,the presented method can obtain free-field sound pressure levels within 50 Hz-10000 Hz frequency range.The free-field sound pressure level correction values acquired by microphone mounted on an acoustically hard surface are about+6 dB in low and middle frequency ranges.The sound pressure level correction values acquired by pole-mounted microphone are about+2.6 dB in middle and high frequency ranges.By the presented techniques the airplane flyover free-field sound pressure levels can obtained reliably and conveniently.But the proper noise measuring method need to be selected according to the flight test conditions.

关 键 词：声学 飞机噪声 噪声测试 地面影响 自由场声压级 

分 类 号：V216.54[航空宇航科学与技术—航空宇航推进理论与工程]